The World Health Organisation’s 6th edition of semen analysis has become the fundamental investigation and subsequent evaluation protocol for the infertile man.
If routine semen analysis is abnormal, it should be repeated. Once the repeated semen analyses demonstrate a sperm concentration less than 15 million spermatozoa/mL, serum testosterone, serum follicle stimulating hormone (FSH), and luteinizing hormone (LH) should be measured.
In cases of absence of the vas deferens on physical examination, patients should be tested for the cystic fibrosis conductance regulator (CFTR) gene mutations. Genetic counselling is necessary before intracytoplasmic sperm injection (ICSI) and IVF.
Genetic assessment for Y-chromosomal disorders should be considered in men with normal hormone concentrations or isolated elevation of serum FSH and sperm concentrations <5 million/mL.
If a Y-chromosome microdeletion or a chromosomal abnormality is found, genetic counselling is also recommended before ICSI is undertaken.
Currently, it is estimated that genetic defects may explain at least 15 per cent of all human male infertility prevalence.
One recent meta-analysis identified 92 gene-disease relationships with at least moderate evidence of a critical role in male infertility.
Theoretically, the testing of all patients for genetic anomalies has not been cost-effective. However, given recent developments in novel sequencing technologies, it is now possible to consolidate one or multiple panel tests in the Next Generation Sequencing assay. This will help to minimise costs.
More genetic research is required to help guide daily practice in male infertility, not only for diagnosis but also for counselling.
“Male Infertility SIG” on ASPIRE newsletter Volume 7, Issue 3 (August 2022). Read more here .
Written by Professors Gwo-Jang Wu and Atsushi Tanaka